There has been a need for bone graft materials with improved osteogenic properties, i.e., bone graft materials that are capable of promoting bone formation. Ideally, the bone graft materials would serve as an osteoconductive scaffold that promotes the in-growth of new bone. As bone growth is promoted and increases, the bone graft material resorbs and is eventually replaced with new bone.
Chitin, the main constituent of the crustacean shells, is a naturally occurring linear polysaccharide composed of randomly distributed b-(1-4)-linked D-glucosamine (deacetylated unit) and N-acteyl-D-glucosamine (acetylated unit). Chitosan is synthetically produced by near complete deacetylation of the N-acteyl-D-glucosamine unit of chitin rendering it soluble in most acids. Chitin has been found to have an acceleratory effect on the wound healing process by increasing the rate of blood clotting at the wound site. Various forms of chitin including fibers, non-woven mats, sponges, and films have been used in wound healing products and show an increase in wound healing by over 30%. Chitosan has also been demonstrated to exhibit antimicrobial properties on various types of microorganisms.
However, there is a need for a bone graft material comprising chitosan which exhibits osteoconductive, hemostatic, and antibacterial properties without altering the structural integrity and/or handling characteristics of the bone graft material.